This section provides background information related to the present disclosure which is not necessarily prior art.
Many conventional processes to metallize a nonconductive substrate include etching the substrate, followed by activation, followed by electroless metallization. Electroless metallization renders the nonconductive substrate conductive, thereby allowing for subsequent traditional electroplating processes. In many such processes, the etching of the substrate is accomplished by dipping the nonconductive substrate in a chromic acid-sulfuric acid mixture.
Many such etching processes predominantly utilized hexavalent chromium. In the past several years, however, the use of hexavalent chromium etchants has declined because of the healthcare risks hexavalent chromium poses. Yet other methods have avoided using chromium in the etchant solution altogether and migrated to other solutions, including Manganese based etchant solutions. Mn etchant solutions have other unique challenges. There is a continual need to further reduce the costs associated with the Mn etchant solution.